For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningRemoval Procedure
Warning: Refer to Cracked Window Warning in the Preface section.
Warning: Refer to Glass and Sheet Metal Handling Warning in the Preface section
Note: Position the vehicle on level ground and move the front
wheels to the straight-ahead position.
Disconnect battery.
Remove air inlet grill ...
Service Publications Ordering Information
Service Manuals
Service Manuals have the diagnosis and repair information on the engines, transmission,
axle, suspension, brakes, electrical, steering, body, etc.
Service Bulletins
Service Bulletins give additional technical service information needed to knowledgeably
service General Motors c ...
Anti-Corrosion Treatment and Repair (Base)
Warning: When applying sound deadeners, or anti-corrosion materials
due care and preventative measures must be exercised to prevent
any material from being sprayed into door and quarter panel mechanisms such as
door locks, window run channels, window regulators and
seat belt retractors, as wel ...